Multidisciplinary Design, Analysis and Optimization of Performance Adaptive Aeroelastic Wings

摘要

A multidisciplinary design, analysis and optimization (MDAO) tool for designing composite aircraft with performance adaptive aeroelastic wings is presented in this paper. The MDAO framework is applied for designing a low-speed flying-wing composite aircraft as a testbed to demonstrate the active flutter suppression for flexible large aspect ratio wings. The Sparibs concept is considered for the wing box design by designing both spar and rib locations with manufacturing constraints in their shape for testbed. Both the structural weight and total drag reductions are considered as the objective functions for the flying-wing aircraft design subjected to various constraints including strength, buckling, stall lift limit, hinge moment and flutter. The worst load case of 3.8G maneuver load factor is used to determine the optimal internal structural layout and the optimal laminate configurations for the wing box resulting in minimal total weight. A hybrid optimization approach is used for the full structural optimization. An evolutionary algorithm is used to determine the optimal laminate configurations for wing skin laminates and sandwich panels, and spar and rib locations. For each population of the evolutionary algorithm, a gradient-based optimization is conducted to determine the optimal flaps resulting in the minimal wing root bending moment as a surrogate for the structural weight. Once the optimal sized structure is obtained, a gradient-based optimization is conducted to minimize the total drag by scheduling its flap rotations during 1G cruise.